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s1axter writes with word that "the data log format for the Tesla Roadster has been reverse engineered and documented, now available in Python. (Python script linked in the post.)" From the linked blog entry: "Not only was I given a $110k car unrestricted I was requested to see what ECU information is available, collect and parse the data from it. Tesla Motors periodically collects information from their vehicles presumably to see what real-world driving the cars see. On original Roadster models there is no method to collect this information remotely thus someone must go out to the vehicle and collect it. The owner of the vehicle saw this and wanted to know what information was collected on these service calls ... Because I am a big fan of freedom to modify a program to fit ones needs, I have uploaded the ... python script to parse Tesla logs."

I was listening to a report on the New porche. The person doing the report called the dealer, and the dealer delivered the 100K+ car to his apartment. Then just left the keys with him. Never checking who he is.

All we need now is a way to plug in the smartphone of our choice, the script ported to phone apps, and a dealer willing to let us take a Roadster out for some test driving. To be a valid test drive, one should get to go until the fuel/power runs out.

All he is doing is bragging about a python script that he himself admits to be simplistic and ugly. The binary format was decoded by two other posters in a bulletin board who also wrote a windows parser but the original guys did not think it warrants any kind of bragging like this. And he is not posting the logs either due to privacy concerns. So unless you are curious about seeing someone's ugly hack of a python script, just move along, there is nothing to see here.

Hey, at least he's not trying to sell anything. This is a step up from the usual slashvertisement/slashnouncement 'stories'. Anyway, I thought building on top of other people's work was still a good thing around here.

I think you're being too harsh. I looked at the script and it's very short and fairly easy to read. How can you complain about that? I couldn't get to the website to download the Windows tool, but I'm going to guess it's a compiled exe (could be wrong), which means it's not easy for the user to edit. By contrast, the user can easily tailor the Python script to fit their needs. In addition, the script also serves as format documentation. He clearly commented sections such as "daily record", "error reco

What surprises me here is that this guy didn't bother simply writing to Tesla asking them for the data format? While it has been changing, particularly in regards to the partnership with Toyota, Tesla Motors has typically been quite open about what they are doing and more than willing to work with the after market & car hacker crowd. They certainly are a small enough company that a simple letter (snail-mail) or very well formed e-mail to J.B. Straubel (the engineering head at Tesla and co-founder of t

An engine is a machine designed to convert energy into useful mechanical motion.

An engine is a machine designed to convert heat into useful mechanical motion.

Fixed it for ya!

I suppose that is true even for an electric motor, although the heat conversion is filters and perhaps even delayed a bit, even if it is solar powered, in which case the heat energy is even more remote and due to incandescence on another astronomical body. But no matter how removed from that heat, you are pretty much spot on correct.

Of course you could also say that an engine is designed to convert nuclear fusion into useful mechanical motion, as almost all forms of energy come from nuclear fusion at some

One car company even 'gives you one for free': you can hit the rev limiter fuel cutoff once a year, any more and you void the warranty for parts excessively worn by over revving. (dammit - I can't find the cite right now. The google is weak in me today.)

The rev limiter is there precisely so you don't hurt anything, once a year would be ridiculous. What it can't stop is people with a manual transmission shifting to a lower gear when the RPMs are too high, which will create an unavoidable over-rev situation.

One over rev isn't going to destroy any modern engine. It's the long term effect that they are curbing. Many very tine bits of damage acquired over time can be hard to differentiate from a 'bad' engine.

One over rev isn't going to destroy any modern engine. It's the long term effect that they are curbing. Many very tine bits of damage acquired over time can be hard to differentiate from a 'bad' engine.

That depends on how far the engine goes above the redline. Sure over revving an engine 500 or 1000 rpm once or twice in its life time won't kill it, but what about 3000 rpm a time or two by doing something like going from 5th to 2nd gear at high speed? Chances are winding it up that tight is going to cause some damage and cause a measurable shortening of its lifespan. It may even destroy it right then and there by throwing a rod through the block or hitting a valve with a piston..

Since the invention of the fuel injector, gasoline has been metered appropriately. Prior to that, cars used a carburetors which tended to run the fuel mixture too rich. This causes excessive washing of oil from the cylinder walls thus causing exponential wear and tear on the engine depending on RPM.

Now days with tight clearances, improved metallurgy, oils, and computer controlled injection; running high RPMs will not have that much of an effect on its life. If anything, you suffer fuel economy.

Now days with tight clearances, improved metallurgy, oils, and computer controlled injection; running high RPMs will not have that much of an effect on its life.

These days they're using the tight tolerances to build torque via intentionally higher RPMs instead of bigger pistons or increasing compression. It saves on fuel and engine size. But the higher RPMs create higher forces on the moving parts, "taking up" the slack the tighter tolerances and better materials gave them. Revving the engine over the manufacturer's published spec still risks damaging it.

You mean they are relying on higher RPMs with fewer pistons to create additional HP. Which makes sense given how some i4 engines can approach the same levels of power to that of a v6. But notice the displacement of these i4s. The pistons are massive in comparison to the smaller ones in a v6. By consolidating your displacement into fewer cylinders, there's less friction robbing you of power.

Running at higher RPMs is not fuel efficient by itself. But depending on the cylinder count and overall displacement, I

Which makes sense given how some i4 engines can approach the same levels of power to that of a v6.

Most I4 engines in European cars are more powerful than American V6 engines. I mean, Ford are still releasing engines based on the ancient Essex blocks, albeit drilled out to 4 litres, but they're still thirsty, clattery gutless boat anchors. Hell, the I4 turbodiesel in my van is quieter and more powerful than most Yank-tank petrols...

I will point out that citing HP numbers is the absolute worst way to compare any two different engines. Horsepower, in of itself, is an almost useless metric for comparison of anything.

Horsepower numbers are a great concept used by magazines and manufacturers for people who generally don't know anything about engines or vehicles. Car and Driver is a great example. Its for people who know nothing about vehicles but want to pretend they do. If you know a religious Car and Driver reader, with few exceptions, y

The only time I read car and driver is in the doctors office, and its usually a year or so old...

now to your point
"Horsepower, in of itself, is an almost useless metric for comparison of anything" -- yes and no, the submitter said "The I4 turbodiesel in my van is quieter and more powerful than most Yank-tank petrols."

Sorry, but if you are making a reference to "powerful", then yes horsepower needs to be considered. Is it everything no, of course not, lots of other things can be considered, but it's n

Actually horsepower is about the only number that can be reasonably compared between different engines. Any engine of the same peak horsepower, when connected to a perfect continuously variable transmission and installed in a vehicle of the same weight, will accelerate identically. Sure, the real world will add variables, but the engine won't be one of those variables.

Try this someday: Run a standard transmission car down a measured section of road twice. One time shift so that the engine stays as close as possible to peak torque and one time shift so that the engine stays as close as possible to peak horsepower. You'll find that the car accelerates much better at peak horsepower than peak torque.

Torque isn't abstract enough for valid comparisons. For example, it's really easy to boost torque by changing gearing. If an car company wanted to, they could simply add

Torque is the useful metric. Furthermore, as HP is directly derived from torque. So if you know the torque curve, you know the HP curve. Regardless, neither provide much meaning without a corresponding torque curve.

Which is faster? And engine with 100 HP or an engine with 1000000 HP? If you can answer correctly, then you're smarter than the rest of humanity. If you can't answer, then you now understand exactly why HP by it self is a completely useless metric for comparison for laymen.

You're conflating several items and are completely wrong. Read my other reply in this read. You're also conflating peak HP/torque with a usable torque/HP band.

Torque isn't abstract enough for valid comparisons.

And frankly, that statement is just dumb. Hp is an abstract and so much so, its useless for comparison of different engines (read original context - which you dumped). Furthermore, HP is a function of torque. So if you know the torque and its curve, you know the HP.

Furthermore, the biggest problem with citing HP numbers is you are citing peak. Peak is

Power is torque. HP is work. You can have a more "powerful" engine despite having less peak HP. That's entirely why diesels are popular for work trucks. But frankly, "powerful" is a highly subjective claim anyways.

There are basically two ways to make horse power. One is by brute force (large displacement; generating torque). The second is by high RPM. Illustratively but not completely accurate, hp = torque*RPM. Typically, large displacement means large reciprocating mass. This is the antithesis of high RPM and reliability. Likewise, high RPM typically means low displacement with and associated lower reciprocating mass.

Classically these two ideologies have materialized as large American V8s versus small European/Asian

My point was that all other things being equal, higher RPMs can yield more power. But you're right, if you can cut cylinders, you can get back to the original amount of power while saving on friction and reciprocating mass.

Since the invention of the fuel injector, gasoline has been metered appropriately. Prior to that, cars used a carburetors which tended to run the fuel mixture too rich. This causes excessive washing of oil from the cylinder walls thus causing exponential wear and tear on the engine depending on RPM.

Now days with tight clearances, improved metallurgy, oils, and computer controlled injection; running high RPMs will not have that much of an effect on its life. If anything, you suffer fuel economy.

I used to drive my 99 Miata like I stole it. I actually tried to destroy the engine. I would float the valves often for the hell of it. This lasted for about 160K miles before I got rid of it (bought it used with 34K on it). Spark plugs indicate a clean burn (nice tan color), valve train and cam lobes in primo condition, and excellent compression on all four. Yup, engine tech has come a long way.

You're missing the point.

The reason an Formula 1 engine can withstand the rpms they do is because of type and quality control of materials, closeness of tolerances in parts manufacturing, how closely the rotating assembly is balanced, and the quality control exerted over the parts used in the engine(each individual part is examined externally and internally for any flaws), etc....

The care taken in building a racing engine cannot be used in a factory situation. It would add 10's of thousands of dollars to t

Someone in charge of ECU software design must have been asleep at the desk. Any engine over-rev on a manual gearbox should be immediately mitigated by applying compression braking. With this in effect, I can't really understand what's the problem. Sure, someone who chose a wrong gear and over-revved the engine will have to deal with effects of braking, possibly doing skid recovery and whatnot. In any case selecting too low of a gear with too little throttle applied will always cause the drivetrain to drag l

Someone in charge of ECU software design must have been asleep at the desk. Any engine over-rev on a manual gearbox should be immediately mitigated by applying compression braking. With this in effect, I can't really understand what's the problem. Sure, someone who chose a wrong gear and over-revved the engine will have to deal with effects of braking, possibly doing skid recovery and whatnot. In any case selecting too low of a gear with too little throttle applied will always cause the drivetrain to drag like crazy.

There isn't enough compression braking in a gas engine to stop over revving an engine in this scenario. For proof of this try driving down a steep hill in a heavily loaded gas engine powered vehicle. What you will find is that even in lower gears you will have to use the brakes to keep the engine from over revving. Then do the same test in a diesel powered vehicle equipped with a compression/exhaust brake installed. The difference will be immediately apparent as a diesel engine with a Jake brake can creat

Yeah, no hit. To extreme abuse will be obvious. Clearly that wasn't my point. In the events you are talking about are called 'throwing a rod' or 'destroying the transmission', or 'blowing a gasket' NOT over reving.

What do you think happens to engine rpm when you shift from 5th to 2nd gear? Engine rpm climbs dramatically. If you're going fast enough it over revs the engine almost instantaneously. In a front wheel drive car the situation is even worse than in a rear wheel drive vehicle as the weight is thrown onto the front wheels increasing the tire traction and making sure engine rpm stays higher for a longer period of time.

What it can't stop is people with a manual transmission shifting to a lower gear when the RPMs are too high

Actually you can. Its called gear lock-out. When shifting to a gear would result in an over rev, the transmission can lock out the gear preventing the driver from shifting to the gear. My car has such a mechanism.

Besides, I've never even come close to noticing the lock-out unless I'm driving extremely aggressive, in which case, it has saved me from down shifting too low. The result, the vehicle is protected from driver abuse which seemingly, only results in extremely atypical driving conditions.

Factually there is such a thing. Just do some searches for "gear lockout". Typically its done on first, first and second (typically 4+1 tranny), or first, second and third (six speed tranny [4+2]), as those are the gears where over rev is far most likely. The thing is, you really don't need a complex set up to lock out gears because all previous gears are also inclusive.

You can hit fuel cutoff rev limit all day long, all year long and your warranty is not voided. The engine has been designed to operate up to that speed by the manufacturer, that's why the rev limiter is in place. Over revving is what voids the warranty, and on any modern car there is only one way of over revving, called "mechanical overreving" or "money shift" -- imagine an engine with a 8000rpm redline, shifting from 4th to 5th at said 8000rpm, and by accident actually downshifting into 3rd. This results i

Hmm, the manual cars I had would simply not let you shift that low. There was some kind of mechanical thing that would prevent you from shifting into low gear if you are driving fast even if you had the clutch fully pressed.

Usually you can shift it into the gear you want, you just have to push a bit harder;)Most cars also try to prevent you from shifting to the 1st gear when you're still going 50 kilometers an hours while breaking for a traffic light. Just push a bit harder and you'll succeed easily.

Yes, pushing harder will get it in gear, but at the expense of shortening your synchros life - much better for the transmission to hold off on ramming it into first until you're slow enough that it slides in easily. Or just leave it in neutral, let the clutch out and use your brakes. When you're ready to go again, just shift into first.

Remember: brakes are almost always cheaper than a clutch or a transmission rebuild.

Hang on, I think there's some confusion here. First off, hitting the rev limiter does not damage your car. If revving at that level was going to cause damage, the rev limiter would be set lower. BMW's older M3 with clutchless manual SMG had a hidden feature where you could enable launch control by a combination of button presses, which would allow you to from rest floor the accelerator and on click into first gear it would launch at max attack. They enabled a feature where after 5 such actions they woul

The redline is the maximum RPM at which the engine is "safe", in that it is within design tolerances. Operating above the redline is possible, but basically at that point they're saying "you're on your own." Cutting off right at the redline would be keeping everything safe, but doesn't allow for the occasional need to go over, such as in the accidental example of missing a gear on the downshift - far better to allow a 5 - 10% overrun than to punish that with an immediate limit.

It could be made impossible on a robotized manual transmission - if it gets a command to downshift that would send the revs too high, it just stays in the current gear, and if somehow it's in engine braking and still going too high (maybe going down a steep hill in a higher gear) then disengage the clutch and shift into neutral - although this could put the whole car in danger.

Any/all rev limiters I have ever worked with have all been on the spark side of the power triangle ( compression / spark / fuel )

Every car with a rev limiter in then engine ECU accomplishes it by cutting the fuel off. If you turn off the ignition, you continue to blow unburnt petrol vapour down the exhaust, where it will ignite in a spectacular killswitch backfire as soon as the ignition kicks back in. It will also destroy the catalytic converter.

A lot of cars with automatics have the RPM limiter set lower than the same car with a manual, because the auto trannies can't take the higher revs, while the manual gearboxes would happily go to twice the engine's max RPM.

I wonder if you could counter-sue through copyright of data. Unless there is a clause when buying the car saying that the company can copy data from your property, it is by rights, your data and when they download this black box of data they are infringing. Given that it is indeed a black box, an even better argument might well be that they are not only infringing on your data, but also blocking you from accessing your own data.

In the USA data is not protected by copyright. Besides, you gave them permission to copy it. As for "blocking" your access to the data: how are they doing that? You have possession of the car and are free to do anything you want to with it.

It would be very tough (read: impossible) to argue that data logs automatically generated by an ECU constitute creative content, and it is creative content that is copyrightable. Furthermore, the data logs would more than likely be owned by the owner of the car, not the company that built the car. Ergo, the owner of the car would own the copyright on the logs (if such a silly thing could exist).

Now, if you got a hold of the ECU's source code, that is a different story, but reverse engineering the ECU soft

I'd be careful with this argument. A painting is basically a mechanical log of painter's hand position over time. A book is basically a mechanical log of a bunch of keystrokes. While driving is mostly utilitarian by nature, there are drivers who "play" with their cars -- do things that are creative in nature and not merely utilitarian. Just like book writing can keep food on the table, driving can get you to your destination, but still you can be creative: play with brake lights, engine revs, etc. A log of

But it's a wicked fast pile of duck shit - it slides by you so fast, it doesn't leave a stain - and that's from a standing start. Besides, there are many overpriced piles of automotive avian ejectamenta - I'd sooner own a Tesla than any other, even a Porsche or ( although my teenage self would shudder to hear my middle-aged self say it ) Lamborghini

I took my Mustang out there about ten years ago. It was fun but I never really got the salt out of all of the places it found a way into. Protip: Don't drive there in early morning except in high summer - the salt is wet and sticks like nothing you've ever seen before.

The Roadster has a governor? I've never heard of such a thing. The main deal is that the RPMs in the engine start getting to insane levels turning the engine + drive train into a huge flywheel which takes increasingly larger amounts of energy (it increases geometrically, not linearly) to spin even faster. If that is a governor, then so be it, but removing THAT governor is simply removing the engine altogether.

The limiting factor is the current draw from the battery pack. Expand the battery pack, and you might go faster, but at the expense of killing your acceleration time due to additional weight.

I suppose you could hook up a Mr. Fusion or some other massive energy source that could kick the car into overdrive, but once you get past 88 mph you would be looking at temporal displacement when that happens too.

In electric motors, current creates torque; voltage is speed. To up the speed you would have to up the voltage. However it will be limited by the insulation between windings, exceed that voltage and it will arc through the insulation and the motor will melt beyond repair. Happens to electric drive trucks down hills; speed past supply voltage motors become generators, keep going self induced meltdown. Add insulation, efficiency goes down, motor gets bigger... Torque has similar issues, More current for

It should be noted that the Tesla engine uses an alternating current motor instead of a direct current motor. In fact, that is why it is called "Tesla Motors" in in part that the original patent for the engine design being used on the Roadster was filed by none other than Nikola Tesla himself, where the RPMs on the motor are being regulated by the voltage frequency. It really is some cool tech, and part of their "secret sauce" that distinguishes what Tesla Motors is doing from some of the other electric v

Going 120 mph max with a 0-60 in roughly 4 seconds certainly isn't the performance envelope of a golf cart.

This is true, but after driving a roadster one of the ways I described the experience was that it was like driving the world's fastest golf cart. The mindblowingly instantaneous acceleration is only encountered in an electric, and the foot-off-accelerator instantaneous deceleration of the electric takes some getting used to. Take your foot off the "gas" in a Tesla and you don't coast like you do in a 4-door sedan, you decelerate fairly hard. All-in-all I highly recommend taking the Tesla for a spin. It

The voltage limits in a typical electric drive system are there due to the battery voltage, not due to motor's insulation. Any motor worth its salt should have its insulation system survive 2-3x overvoltage without damage. Ergo -- no way to "melt" an electric truck motor by going fast downhill, what you may well kill is the output switches (half-H bridge triad) of the power supply.

safe to say, you haven't seen what I have. Many of these trucks are designed for 20 MPH top speed, especially the DC drive, operator wants to send one of them over the edge, just head down the hill with the system off kick it in about 30 MPH, and it shoots flames about 20' out from the wheel motors (have to see if I can find one on youtube, it is impressively bad.) Granted the DC drive starts with the brushes, once it carbon arcs them they start the cycle and they will inevitably start melting the insulati

The motors generate a back-EMF simply because they are turning. You don't need to have anything attached them at all. If the intra-winding insulation on the motors were to fail due to overvoltage, you'd achieve that without anything attached to the motors -- spin them fast enough, insulation breaks down, windings short together and start dissipating mucho power, flames shoot out. Try it out: disconnect the motors, hook the output to a voltmeter (via a fuse!

The gearbox is even still there, but modified for only one set of transmission gears. Yes, the Roadster was supposed to have at least two sets of gears so it could in theory reach higher speeds, and I'm not entirely sure what the original top speed was supposed to be, but I think it was higher than the current 125 mph. Since this is well above the legal speed limit for any stretch of highway in America, it wasn't seen as a pressing concern for a production automobile trying to meet ordinary consumer deman

But is that limited by horsepower or a governor? Makes a big difference. Plus, 125MPH is still 45MPH faster than the legal speed limit anywhere in the US. Not that that means a damn thing. But anyway, as long as it's not a horsepower limit...if you're spending that kind of money and plan on going that fast, I'm sure you can find a way to get it reprogrammed. And since it's right at 125MPH, I'd imagine it's a programmed limit and they're using U or H rated tires. Could be wrong though.